Adsorption isotherms of m-xylene on activated carbon:: measurements and correlation with different models

In this study, adsorption isotherms of m-xylene on activated carbon were measured by time integration of the breakthrough curves at T = (298.15, 308.15, 318.15, and 333.15) K using home-made apparatus developed fur this purpose. At the temperature 333.15 K, isotherms were also measured using a microbalance in order to check the accuracy of the proposed apparatus. As expected, in keeping with the principle of Le Chatelier, the m-xylene loadings were observed to decrease with increasing temperature. Activated carbon was used as the adsorbent because it typically exhibits high adsorption capacities and shows potential as an adsorbent to effectively remove volatile organic compounds (VOCs) such as m-xylene. In a second step, the experimental data obtained were correlated with different existing adsorption isotherm models such as the Langmuir model, the Freundlich model, and the Dubinin equation. The Langmuir model was found to be well adapted to describe the adsorption of in-xylene onto activated carbon. (C) 2000 Academic Press.